1. Field of the Invention
The present invention relates to methods of protecting electronically published materials using cryptographic protocols. The invention also utilizes special "agents" of software or hardware to have individual requirements for display devices and/or printers to effect decryption and display or printing of the documents. These methods are directed to inhibiting illicit republication or copying of electronically published documents.
2. Information Disclosure Statement
Cryptography and Identity Verification have been described in the prior art in conjunction with computer transmissions through networks. For example, U.S. Pat. No. 4,393,269 describes a method of incorporating a one-way sequence for transaction and identity verification and U.S. Pat. No. 4,995,082 sets forth a method of identifying subscribers and for generating and verifying electronic signatures in data exchange systems. U.S. Pat. No. 5,144,665 describes a cryptographic communication method and system. Although these patents use cryptographic techniques and key identification and access methods, none teaches or suggests the system claimed herein which involves a combination of techniques to prevent illicit copying and to enhance tracing of original users.